EIPA (L593754; MH 12-43) is a TRPP3 channel inhibitor with an IC₅₀ of 10.5 μM. EIPA (L593754; MH 12-43) also inhibits Na⁺/H⁺-exchanger (NHE) and macropinocytosis. IC50 & Target: IC50: 10.5 μM (TRPP3 channel)^[1]
NHE^[2]
Macropinocytosis^[3]
In Vitro: In the presence of 100 μM EIPA, 10 μM benzamil, and 10 μM phenamil, ⁴⁵Ca²⁺ uptake decreases from 79±9 to 46±4 (58% remaining), 27±4 (34%), 29±5 (37%), and 38±4 (48%) pmol/oocyte/30 min (n=6, P=0.008), respectively. It is found that EIPA, benzamil, and phenamil rapidly and reversibly block Ca²⁺-activated TRPP3 channel activation at -50 mV, with IC₅₀s of 143±8 (n=36), 10.5±2.2 (n=28), 1.1±0.3 (n=30), and 0.14±0.04 μM (n=25), respectively^[1]. The number of autophagic vacuoles increases dramatically in the HAE and HPE groups after EIPA treatment compare with the HAN and HPN groups. EIPA regulates the initiation and maturation of the autophagy associated with amino acids in IEC-18 cells^[2]. In addition, the uptake of cinnamoylphenazine (CA-PZ) and neutral red (NR) is inhibited by EIPA^[3].